SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bafb138babe2873fa896d143c27ed65f4b31bee19dfa364093b1a69117bf65b' 
  AND token = 'PWfZOSYGmrvmp3drI5Gx2Q216mMzkOD5t3qnY8FUuU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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