SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '54e4681275da53af21e8c20c22bf2f8bd48c7e3aa819875254f271446b1dfdf0' 
  AND token = '0ysXaPUzflZV1gtiHLXzwhPuSZwPptfmTaQsogxSexs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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