SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06d7f1e486ecd83609b3b5fb562d6ecdc9391b1b88d7181469cf31a7e3d8c9e2' 
  AND token = 'y2ynCkd4Za7GUk8aJxqp23YNkRla9S5jECrdciyUIRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}