SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10a1ec1042e40e031859dca6f07de454e85e29d04cd98a369806f5ee6d8f0b31' 
  AND token = 'i4Vtm91Z6tvu0SuQ7Us/KQY0Ntssu4B6k7y+9GPt8LI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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