SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9997cb0290b665cfcbb66a0a6c56138d3e61b877192f87686d84071174e1caaf' 
  AND token = 'SYWv9RNJiV5kh3bhuxfo0+f/mBWAYHxCV64q6M7mFVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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