SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '116374e9353731f10280bbe26d74900008d2b686cddcb7d11828b16c4c7f6db9' 
  AND token = 'KO4lSi1JLhCpyrNgiPCzTEIFnPgu17QFJoBBEauLdec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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