SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6ba63409a3e625d75e3515dd266bf5997d022dfb7a466884b9628dd5d7f051d' 
  AND token = 'ByZDr3ZTQVX7ed51gjcCUzPNoExmw6X0Teq3lW/QX2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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