SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd0f2616270050dbf4bfa608362faecc4fc2291ace2a4a10ec5fa4ac960816a' 
  AND token = 'QTOqzVMdMq8V8I0V1Y9OLUsPkNmY9/F4lsXDU2axBX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00122

JSON explain

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