SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '18048593e57fa05adf5ddd7443585fc756c562d0649d82896ec7696ec2f519e9' 
  AND token = '5AUWXlGlpTdRebgj0dRA8n21kKYMBdwEJCWVLWmzIsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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