SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9e2c7d038871f62afd046d3c0383ff619081cda7b7f49f0b9e206f049ac1a3a7' 
  AND token = 'G/oFZMWhnFgH4VE10cN0MFeqUntB37czwWuNtuYvz+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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