SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '982e2d0c7aac22ebc7cbd7395a498e14b63599b20233050825c5da0652191792' 
  AND token = 'hbrOnQP3LTfij+ehtwQH1K191QyLZ2W6OpVbfUQpZNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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