SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '656d38e105527d08a7d84b8bc0fb62c97e6642792c11c9043269e62dcb9f51a7' 
  AND token = 'ivcRh78tCjjhfflpCxhl0IJrPLMXe/L53nPppnfqIK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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