SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '122e19486c16382cc24e4afd9564f38ff22f650cc29ccfd3f1a74f88a83f1440' 
  AND token = 'CrjL9S9CDJAA6QvEN2aw//ENYpl8I2GAZ86RC8Xte3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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