SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2eb67df44e6a5f87d3571984ee6d5e598d8bd25c031bea925bd4fef94a931397' 
  AND token = 'MV/f2gBlbnzUOqCyKemzswxMCuSHyntDp7q2jgmWPp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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