SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa2b7b6b178acaabd201dd2195e866f236f98bed317f2d66781df904f2bd10cd' 
  AND token = 'FVhlxSR51orivDo8GvC3B5/uJ8Df65bgTHL02JcqSWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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