SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0f67c00596a2b6a5449610ed0f4892dd1f8a4b16d5dcfc1eb1da2606d02f9886' 
  AND token = 'VlH2LAIMn0zgHrJbU3/wnGlWehJoXwQd461mm5bnhHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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