SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3786b85fcba230aa943f7de233711074dac350be573c6ba9b7529fb5d752f4b6' 
  AND token = 'e/bA5f/tflyuwssUGY5izDKe+WB/C0yctaUvF84Ck/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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