SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a529cf1e7a00ad8a29cc7fd569c9b767390a4adada51082cd3bd27a8aec18656' 
  AND token = 'eU5NuDDz1Y62F14AwQWYHFyhWYilvasQUtjYfjNHFO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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