SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea54d81c21f98a83908c856fe3a49a40756d0702abba59abe32fc3952c151dce' 
  AND token = 'hdJ1k50h2dfkHz1yvqmxukXsKNVGBjqT1UO4XpQpdDg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}