SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '057a881d02ba76d21e7f3ebe66cb6734f2661d8765d54562f4f859bd7aa2e258' 
  AND token = 'awCvV+KLAzfvfp0e9S5gwFtUMrCGeYpgUWfjRApFqss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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