SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '111630844834ef387b7bd653a1177c5645b323e7abee0ad872d7ad055efbb03e' 
  AND token = '/ub18NXpnMqpwJQLmYSF+sNHpgZx+Bl89dGAjeAmqh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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