SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a2dcf7c5d9c12092d8cb36b481771cf4fd2fd146d08ba3cc48082f77b214b5f' 
  AND token = 'ASvPBmpLf/vJ9KnG+vohjxIyjLs/2ePaPg/x+tcOTjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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