SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0d0277a73acdb828034e6d1c060925c37a02f8b6321ab170291b4c01beaf51c' 
  AND token = 'y7Iha+qMYrng9D580XaHQXa3gSVWsHecfRNYqCwnonA=' 
  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"
    }
  }
}