SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbfe976f243b8f09dd12870dc0f04507cd00f51326ed6e62989f23bcf9baa250' 
  AND token = 'afHVe4elzAAfMICl8aLwnR77QECDfYAUTB57KFoDHSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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