SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f5aab4d1c40e68d1abb239866f528abf3e92a48dd3b2756dc9711803c66617fb' 
  AND token = 'QpaMQP1BT6ywOIOJ/eKyp2m2Jbw+UKH8bSVdameCiS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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