SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94949f3ee5402b85a26da2f86d1d9bb1a6f4e12fef07a60e271a05a66ca5b516' 
  AND token = 'n0/Ce29BodtQzynZ8USkA47QPabsp4oCvKV2u77cXhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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