SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5148b34c1f905bbf5fa9b3fa0a896ce0d8d9334238fbcda4d5f3dee34860cb94' 
  AND token = '61kjfCKMyYQVj77xvUskbixH1qvhNqDTWBi1Ttak8DY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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