Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4412dc3bc3453bdcf91cdbfe3fdcc7a29cb1db52d4caaf41bd8d963ad40321d0' 
  AND token = 'cI9AG95bNgEzch1p6F+9oL4d8Ek6rtNcNZ05x8fYMBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}