SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63bb06b435352b3de918278b1f7f701879442647e42f06ae8cb634bdcd38b446' 
  AND token = 'WTM6/TrvD1KHcL5nEHLubwyyLXmVJmuIHZjWGsaAfiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}