SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7d2597d1e07acdcfe77be07eaf87a782262570ad7fb345c76c371c50f9c4640c' 
  AND token = 'UjX6DzQZZXfgEhoRFtSm+bJkKujk8uSIP0odCM/TPsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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