SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '561f673ada18e0b0f3168217e1447901bcb08d2fe9ba024c6ea32ab217fa0740' 
  AND token = 'FVPkgiJp3P1oAuI4U6XOYe5/BUwqoYWpGTMTML5aKQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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