SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d639485f248fb9b390e028fb763e3e4fec314e604a65eabb1170bf08016d28f' 
  AND token = 'V0u8c7HWl90UAuRGx1TuIK7+VGmv+Q77OXVppZz96Zw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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