Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79f9812a1721a501c2f734e15938fe224a58577ff0ae9efedb1c34ce9bb74388' 
  AND token = '1jrcQuRed2K4ZoIvluNK/LdqtdsfoHT2LlYN/+sn28o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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