SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a056be8ce09ab83aea518f7b427bf11e6ee6d9e37f0f3b946657338518e62fbc' 
  AND token = 'eEdwVJS8gwaKU7/KBp9vqqJpoVGgjTX4ukfTC5AHpmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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