SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a775cd514ff76634487e6c01c1adc6bcc2be44adad478d696a30f7fd42b569da' 
  AND token = 'DpR8r4kIRr04vGHCR9GQ4z/xIvnKPL6DSLJ4hEkEmfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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