SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c23850adaa5eb4e587c5c1fc380bfc6bc983573131c78a2ee6d9dfc7c010658' 
  AND token = 'CZeY1jbHw1OK8KRsZBUnS3G13Lm/0A7io13KGLFlEUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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