SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8495c5a2a8c78763162645e6f84fc3c2879c08c81a99bd5529be6e85e1786a74' 
  AND token = 'LJ91Hz/hPaoquscz1OABTWOJ3gfXRi5YP44+vpE5aso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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