SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6a695340f26d1b1a8b79c0ea435d9efe77ed9279fdddee88797a73426e0fbf6' 
  AND token = 'YKpqMsGvjZu11fPZLHvCjixBjqi9+Kp0m0bicr67GzE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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