SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21946051250807b01d9bfe36f277fd6e6ae7c595e0ea5d14cb595048e0230821' 
  AND token = 'C0voKmnrSk7gwwN80qdnaaKVTbsG5zR60ljJacXz5fU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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