SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34bafd702ea4d1c98c93459e8e41d2a170cc0091b5eb35ae40472da9d4e1449e' 
  AND token = 'ftcz9W0JIP+vix3OnERRLkLgtggZDdpKS3qLEL4BEeY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}