SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e091400ca4fcf9ffc2c4b817fed98893ac92be42225da16c768361838df63726' 
  AND token = 'E8IowGW7Ovgmb5ao9ddK6tPTfQ8HVwiJ/u37ucdUCBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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