SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c69142ced5d7f037621643c61066b7ea41c32112c2f20759030434abbe533343' 
  AND token = 'zATSIwhAA35aFNW8Dp7TlfD/lsMrvc8uxf+wZ3f9Pm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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