SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '68f446d9d54804df9b81e368181f8f8dc799272cc903dabea4b9fc072fdc982c' 
  AND token = '5hSLPb20i5SeW9nVI2v4Gsj0d4pMyhFvZmzZwgiVJas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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