SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fac0fa483fef6f687843eb613bc2200e754bc8c9fdbba08cab460c772918aed' 
  AND token = 'a7rHzJIEJX7MX7QSurL24JvdfSziCVO7aYq6t6mwRiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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