SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc5fa0326a57b0d6cd5c9774c9be11a70095f61d88eb0f2d39e7d9e7cfe1b5c5' 
  AND token = 'wuDR1dNGA6co0pUDQ+w2YARbyOCvxVXL90HXpRShrG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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