SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cc1095cb7b5346d38496fc3d1f559ada613d51c5887235b95447e709a1f0ea7' 
  AND token = 'y6KAsWjLWXvsZhhh5njqRV5Ynz22/QFg6T3RISRD4hY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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