SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72b98817565fdfb6910f1bcc8bccdd3d547e90d67f35aff6c8b75d4445848e4d' 
  AND token = 'ZNR0J4WpfJyRQHOiMm48Q5BcbEPvGamBNActMF6nE4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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