SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9787a513902e03d5ab2d45e0147ee81a4a7af12a4e5d80d605fd17db36e4677b' 
  AND token = 'VGFAvXbk/Ny8fFHUu4P1zQuKIoqwrb6WoOxSm2in0to=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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