SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5ba73438aacf577db6f8646674c1a62f8c8f0115305e656fe1c43db3ab93ea15' 
  AND token = 'JoO8APUvPBkJt8wYHREfB4VIylUrTs9jZOCB64jN5s0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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