SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d867c59dbdb397bc605ef6116e7c6918c44ec2119cda8ca27c01c38e79123c8' 
  AND token = '+icU4cXxWcOwXfXvYVVmsh63ptUiiv9u1MJTtvt94E4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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