SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd53bc6cd1bf1e1eaa6ef5fbec0fa035ecb9e5de0e85b9bc24b3294eb3fb8abc' 
  AND token = 'RfNNV3Kf7lVJnQQlRTyFrCxk0UVdFEQHxnLQGZtO3KY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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