SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14e6ed55c277a9738f6d2f0886e12b594004c6b8f091e74a841147d1ea1bdaa3' 
  AND token = 'wOSVGxJfkiHzomLe++VrXsfqD/h4Slh9SKP360pp5ZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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