SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7b89fd0cb1a1652ee015dc40cd63c695cf6898357998adc605faf7c92160ede' 
  AND token = 'efEhXrV+kwFXuEeaPYYJsxD3Aq/JZFHULxVwE2KpoHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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