SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8d0c26ef05bfb62cd97266bcf478f8aa17498a6f684defc2c38b74943410b26' 
  AND token = 'Oui9daxYsFIxcslIm5D6rW+wirW9x/U+1P8lMeaW8t4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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