SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a830a461dac38982f2bc082ba0d96ecc80e2f686aff645893097c47382192ce4' 
  AND token = 'zYzSHonJrArkFC2KdjYuFDxj2LwsHy2cDOyAs5qSnVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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