SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd64ec15b237fdcc978dc4c3f21040f52210630b422d3a54952a5c10f28aa73af' 
  AND token = 'uIoRcO7cMSXhzDstNifGcIKAtSArjvmunGmzUBqQkRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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