SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '132896548533ae8067ddd19342d472923dee5c63555c1a282f957fb324c5f9c1' 
  AND token = 'ld7Xvlz9XFok9XTKc2pTVF2cTuk6QR3dehXeuDtiRMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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