SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b86f0f1543037fe6895c75577cb54522d97fc078f18d94b0cca99622c04f84a2' 
  AND token = '+G+uPQTM5nuzKqQmyUR7bZpza5e64/JupOdzwAzKZZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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