SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6497272eb97c14453dafaed299cc4c9339309583bf6026a2235e33640f97ebd' 
  AND token = 'No6wSyw4tBfaZmjRKG8L2/5dbz3IB1Le6aVHR161pJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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