SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63aedf16cd938609371cb4fad6f801bac900d67e54633dff2c6afffeff05c14a' 
  AND token = '6CKJlCO6gZ5Hme04KcetfiDlyUHFCdBzLjii7ouZFOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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