SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '12e7a9fd891a2a384370bf1b600d8cc3e484e7a55d23663de601d5b7bb1ce0bf' 
  AND token = 'CxsvqgwmYGrSzQjE4aHHxUrzS0h/8OofD07D4wx+LhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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