SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be67d7b173b2e9c3bb9c42e6a832f644d3548b621ab8b5446f5c02e7a974ebb7' 
  AND token = 'IbhMXeSPJMJrazIhktC5mLvFslIGFY6Qzrbv0xvP+yQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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