SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5f9cc300af97f4e6c3309123fd4c58dea0707d6efcabfba91762da0d51b99c3' 
  AND token = 'Moyx6sr9rLok5H8B9GbO2ZDtijIKLoekNfCbQCZrY5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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