SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4854e675206e3ca81685cbfe325d2f908cb088a33d02f82ad8d5df1b4b2c6fc5' 
  AND token = '9ZudNDvE02KdCw0Gc9NtHj1K+0GcSB7GJWvOJLBwQs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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