SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c570eaad0c441e3b1e261b32b82442e0aa61a48fbb469e2b8383d31f528fcc7' 
  AND token = 'khYKomCRISmoblZzpqGpoJ9bMLnXdVyctaLDQB0qcYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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