SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '740c9f1c6abf9462f996388d951eaa3a3f537c7117d4c09471d0953d689dcc38' 
  AND token = 'eQkO+qG1qr9C/l80QoYfQKEBUCtE2/soR82IIpj+RRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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