SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f66d752d1fb8e31c407cb99022a0921010eba6b3db7256a2cfab09adfb691b3' 
  AND token = '/W0IxB6fiXlGYPCoYAFuF5CZzX1+I2ODMl1cQLBPwJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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