SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bbae103014a78306a2685f90514a275bca16f22e0fb2951c01c960304a16a2b' 
  AND token = 'zdrFcgqNSAaqY+pwcokhiLjHZ5vbBnfVNON7bz3tOno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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