SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b0be4894365f2ac1d4c294b0984e28f60ddd03b743fd07b4414f88ca76bf1bc' 
  AND token = 'vQ4wuTdZzoQQosFTlxYfOHs4fM2cZ8ZcIvi/ApAE+Es=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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