SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bf0a0875f43d42391be44005937c035676d1a5162f051d0c0be30eb0368a1a33' 
  AND token = 'Hi6UrVxNeLRCmONZcZwg86TfmiX+2r/sRJtjzP9y0TQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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